Transportation Engineering Commons^™

New Insights Into Dynamic Evolution Of Colloidal Network Structure During Early-Age Hardening Of Cementitious Materials, Hengrui Liu, Kaiyin Zhao, Shipeng Zhang, Hanghua Zhang, Shuangshuang Liu, Lucen Hao, Hongyan Ma, Kamal Khayat, Chi Sun Poon

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The evolution of microstructure in cementitious materials during their transition from fluid to solid state plays a critical role in determining their ultimate mechanical strength and overall performance. This hydration stage primarily involves a dynamic densification process occurring within the colloidal network. However, the field of cement-based materials currently lacks a comprehensive theoretical framework and associated parameters capable of effectively characterizing the specific structural regions within this network. In this study, we propose an Improved Particle Linkage (IPL) theory for describing the strength, types, and quantities of particle linkages within colloidal network. The IPL theory classifies the internal network structure …

Dvr Service Evaluation And Fee Sufficiency Study, Mallory Brown, Andrew Martin, Jeeyen Koo, Jennifer Walton

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet’s (KYTC) Department of Vehicle Regulation (DVR) administers numerous fees and taxes. Many administered by the two divisions in DVR — Motor Vehicle Licensing (DMVL) and Motor Carriers (DMC) — have remained unchanged for many years despite salary increases, the adoption of more complex and expensive technologies, and inflation raising administrative costs. This report provides in-depth assessments of 10 fees and taxes (selected by division administrators). Six are administered by DMVL — certificate of title, duplicate title, vehicle title history report, additional registration fee, reflectorized license plate fund, and trailer registrations — and four are managed by …

Autonomous Vehicle Adoption Behavior And Safety Concern: A Study Of Public Perception, Fatemeh Nazari, Mohamadhossein Noruzoliaee, Abolfazl (Kouros) Mohammadian

Civil Engineering Faculty Publications

Realizing the economic and societal benefits of autonomous vehicles (AVs) hinges on widespread public acceptance. However, existing research offers limited insights into two key behavioral factors shaping AV acceptance, namely, perceived AV safety concern and travel behavior, the latter reflecting how heterogenous mobility patterns influence the AV acceptance. These factors are often treated as exogenous, limiting insight into their true behavioral interdependencies with AV acceptance and their distinct behavioral roots. This study addresses these gaps by introducing a recursive trivariate econometric model that jointly estimates AV acceptance, perceived safety concern, and current travel behavior (proxied by annual vehicle-miles traveled or …

A Simulation Framework For Edge Lane Roads And Bicycle Shared Roadways, Nick Sauciur

Master's Theses

Edge Lane Roads, also referred to as Advisory Bike Lanes, are a shared roadway treatment that designates space for cyclists while allowing flexible use of the roadway by motorists. They are commonly applied on lower speed corridors and can be used both where roadway width is limited and where agencies seek to manage vehicle speeds, clarify cyclist positioning, or improve shared roadway operations. The configuration provides visually designated space for cyclists while allowing motorists to encroach into that space when yielding to opposing traffic. Although interest in these facilities is growing in North America, quantitative tools for evaluating their operational …

Impact Of Femalized Kinesthetic Learning Model On African American Middle School Girls’ Career Interest, Mercy F. Fash, Andrea Ofori-Boadu

Journal of Global Education and Research

Engaging African American middle school girls in out-of-school-time (OST) Architecture, Engineering, and Construction (AEC) programs can boost interest in male-dominated AEC careers. This study adopts Lent’s Social Cognitive Career Theory to evaluate the impact of an OST feminized AEC kinesthetic learning model (fAEC-KLM) on the career interests of this demographic. Through a qualitative research approach, fourteen (14) African American middle school girls from Guilford County, NC, completed pre- and post-interviews on how fAEC-KLM interactions influenced their AEC career interests. Inductive thematic analysis was carried out on transcribed interviews. Results show that effective components, such as lectures on AEC, bridge construction …

Advances And Challenges In Nano-Modified Cementitious Composites: Mechanisms, Dispersion Strategies, And Impact On Mechanical Properties, Fatemeh Mohammadi Ghahsareh, Pengwei Guo, Nusrath Jaha, Yi Bao, Kamal H. Khayat, Weina Meng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Nanomaterials are increasingly utilized to enhance the mechanical properties, durability, and functionality of concrete materials but face challenges such as agglomeration and uneven dispersion in cementitious systems, which can offset the intended improvements. This paper reviews the advances and challenges associated with nano-modified cementitious composites, elucidating fundamental mechanisms and highlighting strategies for overcoming the challenges through experimental and computing techniques. The reviewed contents include (1) the classification of nanomaterials commonly used in cementitious systems and the mechanisms through which they enhance the mechanical properties of cementitious composites; (2) challenges of nanomaterials such as agglomeration in water, re-agglomeration in cementitious systems, …

Fiscal Year 2023 Fhwa-536 Report For The Kentucky Transportation Cabinet, Doug Kreis, Candice Wallace, Bryan Gibson, Sarah Mccormack

Kentucky Transportation Center Research Report

Every other year, the Federal Highway Administration (FHWA) requires that states submit a Local Highway Finance Report (FHWA-536) to the agency. This report summarizes data on local highway finances and is used by FHWA to evaluate relationships between and changes in revenues, expenditures and investment patterns, and financial trends. This report presents information submitted by Kentucky in its fiscal year (FY) 2023 FHWA-536. Total receipts from local, state, and federal sources used for road and street infrastructure equaled approximately $1.11 billion. Local sources of funding accounted for the largest share of total receipts (47%), followed by state government sources (45%), …

Kytc Digital Project Delivery Phase 1 Summary, Rachel Catchings

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) launched its Digital Project Delivery (DPD) Initiative in September 2020 with the goal of expanding the use of digitally formatted plan and project information throughout the transportation asset life cycle, from project delivery through asset management. KYTC retained Kentucky Transportation Center (KTC) staff with expertise in construction and design to facilitate DPD implementation. This document summarizes DPD-related efforts undertaken by the Cabinet over the past five years. Key activities completed during this period include a survey of Kentucky Association of Highway Contractors members to document their perspectives on design file usage and preferences, coordinating multiple …

Kentucky Cdl Adjudication Pilot And Compliance Needs Study, Jeeyen Koo, Andrew Martin, Jennifer Walton

Kentucky Transportation Center Research Report

This report examines trends in how Kentucky District Courts have adjudicated charges related to commercial driver’s license (CDL) and commercial motor vehicles (CMVs). Using court data, researchers evaluated historical patterns in charge filing volumes as well as conviction, dismissal, amendment, and diversion rates. Between 2002 and 2024, conviction rates declined and dismissals increased. Convictions peaked in the mid-70% range in the early 2000s, but fell to the mid-50% range by 2024. Speeding and other serious traffic violations — many of which are advanceable offenses — were dismissed or amended at rates that could have substantively affected the integrity of CDL …

Fiscal Year 2024 Fhwa-536 Report For The Kentucky Transportation Cabinet, Doug Kreis, Candice Wallace, Bryan Gibson, Sarah Mccormack

Kentucky Transportation Center Research Report

Every other year, the Federal Highway Administration (FHWA) requires that states submit a Local Highway Finance Report (FHWA-536) to the agency. This report summarizes data on local highway finances and is used by FHWA to evaluate relationships between and changes in revenues, expenditures and investment patterns, and financial trends. This report presents information submitted by Kentucky in its fiscal year (FY) 2024 FHWA-536. Total receipts from local, state, and federal sources used for road and street infrastructure equaled approximately $1.27 billion. Local sources of funding accounted for the largest share of total receipts (50%), followed by state government sources (41%), …

Characterization Of Sediment Loads And Size Distribution In Nebraska Roadway Runoff, Bruce I. Dvorak, David M. Admiraal, Pavel Shrestha

Nebraska Department of Transportation: Research Reports

The Nebraska Department of Transportation (NDOT) must manage sediment, and pollutant loads from roadway runoff to meet stormwater regulations. The SAFL Baffle, a hydrodynamic separator used by NDOT, depends on reliable estimates of total suspended solids (TSS) and particle size distribution (PSD). However, limited data exists for Nebraska roadways. In this study stormwater runoff was monitored at four NDOT-maintained sites, two in Lincoln and two in Beatrice, over 1.5 years to characterize TSS and PSD and to evaluate SAFL Baffle performance using the SHSAM model. Results showed large variability across sites and seasons. Median TSS ranged from 158 to 580 …

Assessment Of Winter Maintenance Performance Objectives Using Maintenance Decision Support System, Curtis L. Walker, Mark R. Anderson, Aemal Khattak, Thomas Kauzlarich, Abdul Farhan

Nebraska Department of Transportation: Research Reports

It is important for transportation agencies to assess their winter maintenance operations performance to identify areas for improvement and/or resource investment to maintain optimal levels of service, mobility, and safety. This study explores nine winter snowstorms in Nebraska during the 2023-2024 winter season across 20 road segments, 12 of which were along the Interstate-80 corridor. Datasets explored include meteorological information, traffic mobility insights, winter maintenance operations activities, and road conditions before, during, and after the periods of accumulating snowfall. Statistical analyses explored correlations and quantitative relationships among these datasets, while visual dashboards were developed to promote more qualitative considerations of …

The Effect Of The Socioeconomic Variety In Greater Cairo On Transport Mode Choices, Rafik Yanni

Theses and Dissertations

In the last decade, Egypt has experienced a noticeable upgrade in its infrastructure investment, implementing a lot of transport projects, especially in the Greater Cairo region. In a city with over 20 million residents, variations lie in socioeconomic elements like income, age, gender, and neighborhood, which shape people’s choice of mobility modes based on their culture and lifestyle. The questions then become: whom are these new projects targeting? What are the barriers to using these services? And is there any willingness to change commuting habits if conditions changed? This thesis investigates how the socioeconomic variety in Greater Cairo metropolitan region …

Trip Generation Model For Mixed-Use Development In Klang Valley, Malaysia., Goh Boon Hoe

Student Works (2020-2029)

Mixed-Use Developments (MXDs) are single development projects that integrate and interact with different land uses, such as offices, retail, restaurants, entertainment venues, hotels, and/or residential areas. MXDs are internally connected, allowing users of different land uses to share internal streets, walkways, driveways, and parking spaces. Traffic is estimated to be reduced with such developments. Currently, in Malaysia, there is no standard procedure to estimate the MXD trip generation rates. The Malaysian Trip Generation Manual (MTGM) 2010 is the guideline used to forecast future trips for a single land use and hence, by summing the trip generation rates for multiple land …

Optimal Placement Of Electric Vehicle Chargers: A Mixed-Integer Linear Programming Model, Joubin Zahiri Khameneh, Emmanuel Fagbenle

Faculty Publications

Electric vehicle adoption is growing, but New Hampshire lags in public charging infrastructure, especially in rural areas. This gap increases range anxiety and economic inefficiencies. In this study, we developed a mixed-integer linear programming (MILP) model to optimally locate new electric vehicle chargers statewide, maximizing coverage and equity under budget constraints. The model includes geographic coverage requirements, population-weighted equity, capacity limits, and a $28 million budget. Moreover, the model recommends 855 Level 2 chargers and 149 Direct Current Fast Chargers (DCFCs) across 247 ZIP Codes, nearly doubling public charging capacity and achieving 98.8% coverage within defined service radii. The plan …

The Rise In Height And Curb Weight Of The Top-Selling Vehicles In The United States From 1991 - 2025: Implications For Engineering Design And Vulnerable Road Users, Samuel L. Steinman-Friedman

Civil Engineering Theses

Road fatalities are higher in the United States than in other high-income regions. In 2024, 39,254 people died on roads in the United States compared to 19,940 in the European Union. These two regions have comparable exposure metrics, such as population size, roadway network length, and fatalities per mile traveled. Light trucks dominate the U.S. market, whereas hatchbacks are prevalent in Europe. The trendline of the average height and curb weight of the top-selling vehicles in the United States has increased by 0.24 inches and 23.52 pounds per year since 1991. The average 2025 top-selling U.S. passenger vehicle is 7.5 …

Concord Public Transportation Improvement Project, Jacob Holt

Honors Theses and Capstones

The capital city of Concord, New Hampshire, has been served by Concord Area Transit (CAT) since 1989. Despite continued population growth and economic development within the city, CAT’s fixed route bus system has remained unaltered since 2011. The purpose of this project is to rework the CAT system to provide service that better aligns with Concord resident’s current needs. A public survey was conducted to gather data regarding Concord resident’s needs, habits, and perception of the existing system, which was used in the development of the revised system. The project includes suggestions for both system-wide and route-specific modifications. Key changes …

Evaluation Of Critical Shear Strength Of Soils In Nebraska Based On Revised Cpt, Chung R. Song, Bashar Al-Nimri, Basil Abu Al Sha'r, Dhurba R. Pandey, Jongwan Eun, Seunghee Kim

Nebraska Department of Transportation: Research Reports

This study evaluated the “Fully Softened Shear Strength (FSSS)” of soils in Nebraska based on a revised Cone Penetration Test(CPT) method. FSSS is a unique strength condition that soils show substantially reduced strength during rainy seasons, eventually causing failure of slopes and other structures.

The revised CPT was adapted to inject water at targeted depths, inducing controlled moisture infiltration and capturing real-time soil softening over designated intervals of 30, 60, or 90 minutes. Through tip resistance (qc) and sleeve friction (fs) measurements under “in-situ” and “wet” conditions, the test effectively identified fully disturbed/low strength zones around the sleeve. Simultaneous sampling …

The Use Of Recycled Plastic In Asphalt Pavements: Feasibility Study, Isabella Bueno, Robert Rea, Jamilla Teixeira

Nebraska Department of Transportation: Research Reports

The plastics industry has been actively exploring new end-market opportunities for the more than 35 million tons of waste plastics generated annually. The use of recycled WP in asphalt presents an opportunity to improve pavement performance while reducing the growing amount of WP being landfilled or released into the environment. However, the use of WP in asphalt mixtures poses challenges due to variations in plastic composition and the presence of non-plastic contaminants. The absence of standardized procedures has resulted in inconsistent integration methods and unclear roles of WP within asphalt concrete (AC) mixtures. Therefore, the goal of this multiphase study …

Development And Evaluation Of Crashworthy Approach Guardrail Transition With Increased Span Length Between Concrete Bridge Rail And First Transition Post – Phase I, Tewodros Yosef, Qusai Alomari, Ronald K. Faller, Robert W. Bielenberg, Scott Rosenbaugh

Nebraska Department of Transportation: Research Reports

This study developed and evaluated a 34-in.-tall Nebraska Department of Transportation (NDOT) thrie-beam approach guardrail transition (AGT) with an increased span between the concrete buttress end and the first transition post. The objective was to accommodate a wide range of common obstructions near bridge ends, including abutments, wing walls, drainage features, and utilities. A survey of NDOT districts identified critical obstruction geometries and informed design criteria. Most NDOT districts indicated that a maximum span of about 4 ft would be sufficient, and some preferred spans up to 6 ft. To accommodate a wider range of obstructions, the first transition post …